Develop a MediaWiki extension

Watch it in action

Add and test a MediaWiki extension

Use mw dev mediawiki get-code to add an extension to the checkout used by your selected development context:

mw dev mediawiki get-code --extension Cite

The default Gerrit clone method uses SSH. Configure your Gerrit username first, or use --gerrit-interaction-type http --no-commit-hook for an anonymous public clone when you do not need to push changes.

Fetching the source does not enable the extension. Add it to LocalSettings.php after the shared development settings:

wfLoadExtension( 'Cite' );

Run the updater when an extension needs database changes, then run a focused PHPUnit test from its directory:

mw dev mediawiki mwscript update
mw dev mediawiki composer phpunit extensions/Cite/tests/phpunit/unit/CiteParserTagHooksTest.php

If the test fails, inspect the MediaWiki service logs and repeat the test after the fix:

mw dev compose logs -- --tail=40 mediawiki
mw dev mediawiki composer phpunit extensions/Cite/tests/phpunit/unit/CiteParserTagHooksTest.php

The example uses Cite, but the same loop applies to other extensions and skins. Check the extension’s own README for required Composer dependencies, configuration and test commands. See MediaWiki configuration and service management for more details.

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